... efficiency 3.low noise 4.steady performance Ningbo Excel small ball joints 1.full inch and metric dimensions series ... powder), PTFE liner (fabric with PTFE powder)Out ring: carbon steel, alloy steel, stainless steel, bronze alloyInjection material: ... mixing plastic of PA and PTFERod body: carbon steel, alloy steel, stainless steel, aluminum alloySurface treatment: polish ...